Hi,
I'm planning on cosplaying Chii, and for those who don't know her, she's pretty much a doll.

Because she's paler than me anyway, I'd have to lighten my skin anyway, but I was thinking, would this work:
Getting Proaisde, mixing with acrylic paint and pale foundation (to get a good skin colour) and then thinning it with distilled water.

Then using it on my face to make a perfect 'unnatural' complexion without anything like pores or blemishes.

I don't know if anyone knows any better ways to get a doll like finish, but any ideas or advice would be appreciated.

I don't know what Proaisde is, but I would say no to the acrylic paint. Don't go painting stuff that isn't made for skin application on large swaths of your skin. It's a myth that an actress suffocated from that (we aren't frogs! we don't breathe through our skin!) but it can be hugely irritating and can do weird things to your pores and sweat glands. Craft and art paints aren't dermatologically tested the way makeup is.

I would just go with a foundation makeup that isn't quite your shade. Get a bottle of something really pale and cake it on there. Don't use any blush or highlights or anything. A lot of the time makeup stores will try to sell you foundation in a set of different shades, so that your skin can look flawless but also have natural-looking variations. If all you want is a plasticky android flawlessness (which sounds like an awesome idea for Chii, by the way -- I've seen a lot of Chiis but I've never seen anyone go for android skin with it), just go with one shade.

Foundation hint: use liquid foundation if you want to be in pictures, because powder foundation can do weird things under flash conditions. BUT if you want to experiment, that might be another way to get a nice artificial-skin look.

There's no reason to resort to Pros-Aide for a doll-like complexion. If you think your skin is too dark, simply mix white makeup with your regular makeup (foundation and concealer if you use either or both). Or use a lighter shade of foundation, and set with a white powder. There are multiple tutorials online on how to create flawless skin, which may be what you're going for. The one I linked is for a porcelain doll look, so hopefully it will give you some ideas!

I was going to use PAX on my limbs anyway, but than you for the tutorial links.

@Boreotheria
Proaside is a latex adhesive, and when mixed 50/50 with acrylic paint, applied to the body, it makes a really long lasting body paint. I've used it before, it doesn't damage my skin or mess with it in any way.

Using PAX on your body would be fine. But on your face, it might be a wee bit uncomfortable. Best thing you can do is test things out before your convention/event. Then you can decide which method is best. Good luck!

I suggest getting a pale, almost white powder with a slight shimmer (I would suggest tokidoki's luminosa powder, which I use for this sort of look, but it is no longer in circulation!) and over top of that, blend in a small bit shimmery white eyeshadow (the Balm is what I use here) and use it to highlight your face. This should all be layered over a pale foundation.

I've actually done this before and it looks VERY artificial and doll-like!